The present invention refers to a rolling-mill stand that can be disassembled into modular elements which are interchangeable with other equal or equivalent modules. The rolling-mill stand according to the invention characteristically has a structure such as to enable a simple and fast manoeuvre of replacement of the rolls, using an overhead travelling crane with a hoisting power that is even relatively low, like the ones normally present in all rolling mills.
In addition, the rolling-mill stand according to the invention can be conveniently and rapidly converted from a universal stand to a two-high stand.
The structure of a rolling-mill stand is well known to those skilled in the sector.
Rolling-mill stands of a known type are, for instance, described in the patents: GB-1,183,573, DE-1939485, DE-2506449, U.S. Pat. No. 3,882,710, U.S. Pat. No. 3,899,910, U.S. Pat. No. 3,908,426, U.S. Pat. No. 4,121,446, U.S. Pat. No. 4,715,206, EP-166478, EP-626218, and EP-A704256.
Such stands are generally made up of a so-called container, which supports the stand proper, and to which the stand proper is removably fixed.
The stand (referred to also as xe2x80x9ccorexe2x80x9d or xe2x80x9ccartridgexe2x80x9d) comprises the complex of rolls, mounts, tie rods, and supporting feet.
In a stand thus structured, the replacement of the worn rolls, or replacement for change of rolling xe2x80x9ccampaignxe2x80x9d, must be performed using two auxiliary systems, namely, an overhead travelling crane of adequate hoisting power, capable of taking the stand out of the rolling line, and a robot consisting of a piece of equipment for automatic roll change.
In fact, the replacement of the rolls takes place by translation, using a translator carriage, of the entire container-stand assembly off the rolling line, after which from the container-stand assembly, by means of an overhead travelling crane, just the stand is taken out, which is then deposited on a robot, where replacement of the rolls is carried out with disassembly and reassembly of the stand.
Again using an overhead travelling crane, the renewed stand is taken and positioned once again on the supporting container, and the container-stand assembly is brought back, via translator carriage, onto the rolling line.
As is well known to persons skilled in the field of rolling, in order to be able to carry out properly the entire sequence involved in the operations briefly summed up above, it is absolutely indispensable for the rolling mill to have available an overhead travelling crane having a hoisting power adequate for moving the entire assembly making up the stand, and, in addition, an auxiliary robot capable of carrying out the automatic roll change.
However, not all rolling mills have such equipment available, with the consequent evident inconvenience deriving therefrom for their procurement, both in terms of investments and in terms of arrangement of the plant in the existing space.
The general purpose of the invention is that of overcoming the drawbacks of the known art by making an improved stand having a structure such as to enable carrying-out of all the operations linked to roll change in a simple and fast manner, using the overhead travelling crane and the equipment of the type normally available in a traditional rolling mill.
A further purpose of the invention is to make a rolling-mill stand of the universal type that may be easily transformed into a two-high stand.
Yet another purpose of the invention is to make a fast-clamping and fast-release system between the core and the other components of the stand.
The present invention is concerned with a rolling-mill stand which comprises, in combination, at least two rolls (15) supported by mounts (16,17) having adjustment and blocking tie rods (18,19), supporting feet (20) and supports (20a), wherein said rolls (15) are mounted on a central module (11), while the corresponding mounts (16,17), tie rods (18,19), feet (20) and supports (20a) are mounted together in the form of two side modules (12,13), there being provided a fast clamping and fast release system (21) for stable but separable, connection between said central module (11) and said side modules (12,13).